Stop-valve



L. SG HUTTE. STOIP VALVE.

(No Model.)

Patentd Nov. 27, 1894.

ig mm zff NITED STATES P TENT OFFICE.

' LOUIS SOHUTTE, OF PHILADELPHIA, PENNSYLVANIA.

STOP- VALVE.

SPECIFICATION forming part of Letters Patent No. 529,879, dated November27, 1894.

I Application filed June 26, 1893. Serial No. 478,799- (No model.)

To all whom it may concern:

Be it known that I, Louis SOHUTTE, of Philadelphia; county ofPhiladelphia, and State of Pennsylvania, have invented a new and usefulImprovement in Stop-Valves, of which the following is a specification.

This invention has reference to stop valves, and relates moreparticularly to thattype of valves in which the valve proper is movedfrom and against its seat to openand close the passage by means ofconnections extending to the outside of the casing, usually in the formof a screw threaded spindle.

The object of the invention is to facilitate the operations of openingand closing the valve by relieving the operating devices of theexcessive strains due to the pressure ex erted by the fluid beingcontrolled.

The invention consists in combining with the valve proper at one side, amovable diaphragm or piston located in a chamber which is incommunication with the space at the opposite side of the valve, thecommunicating passage being controlled independently of the Valve sothat the pressures of the two sides of the valve Whether due to thefluid un: der control, to atmospheric air, or toother influences, willbe approximately equalized, thereby balancing the valve.

The invention also consists .in thedetails of construction andcombination of parts hereinafter described and claimed. I

In the accompanying drawings, Figure 1, is a vertical section through avalve and its casing having my invention embodied therein. Fig. 2, is asimilar View showing my invention embodied in aslightly modified form.

Referring to Fig. 1, 1 represents a valve casing provided as usual withports2, and an intermediate valve seat 3, adapted to receive avertically moving valve proper at, by means of which the passage throughthe casing is closed, the valve proper being guided by means of adepending tenon 5, extending loosely through a central socket 6,sustained by arms 7, extending inward from the valve seat. The valve isoperated by means of a spindle 8, having its lower end attached to thevalve by a swiveling connection, and its up-' per end threadedexteriorly and screwed into a nut 9, fixed to the casing, the ex osedend wheel 10, for turning the same.

The foregoing parts constitute a common and well known form of stopvalve, and exceptin so far as hereinafter indicated, for-m no part ofthe present invention.

In applying my invention to a valve of this character, I provide theinterior of the casing above the Valve with a depending annular flange11, surrounding the valve spindle, and forming an .open chamber orcylinder 12. Within this chamber a movable diaphragm or piston 13 isfitted so as to move freely in a vertical direction, and is attached tothe upper side of the valve proper, so as to 'move therewith. I preferto attach this piston by forming the same at its center with an openingto receive the spindle, so that the piston can be seated upon the upperside of the valve to which it is securely fastened by means of screws14, as plainly shown. The chamber 12 at the upper side of the pistoncommunicates with the space at the opposite or lower side of the valvethrougha passage 15, formed in the valve casing, which passage iscontrolled by a stop valve 16, of any suitable construction. From thisdebeing controlled is passing in the direction indicated by the arrow infull lines, the valve 16 being opened, the fluid will pass to thechamber 12, and acti'ng'on the piston therein, will have a tendency tocounteract the pressure of the fluid on the under side of the valve, andthereby balance the latter, so that the screw spindle will be relievedof the se- Vere strain to which it would otherwise be subjected, theresult being that but little power will be necessary to operatethelvalve. When opposite direction, that indicated by the dotted arrow,a free communication boing atforded between the chamber 12 and the spaceon the opposite side of the valve, the conditions as regards pressure orthe absence of pressure at the two sides of the valve will be similar,so that like in the first case the valve will in effect be balanced.

The closing and opening of the valve proper is effected asfollows:--Assuming that the pressure of the fluid being controlled isfrom scription it'will be seen that when the fluid of the spindle beingprovided with a hand a the fluid being controlled is passing in the Ibelow, the main valve closed, and the communicating passage also closed,and it is desired to open the main valve; the valve 16 is first opened,thereby admitting the fluid under pressure to the chamber 12, which willact therein on the piston and will counteract the pressure at the underside of the main valve. The main valve is now opened by turning the handwheel, the resistance being reduced to a minimum owing to theequalization of pressure. The valve 16 is finally closed.

. In closing the main valve the communicating passage is opened, and thefluid admitted to the piston, and will, like in the first case, equalizethe pressure. The main valve is then closed, and the valve 16 finallyclosed.

If the fluid is passing in the opposite direction, the operations ofopening and closing the valve are as in the case first supposed, as faras the order named of opening the two valves is concerned, thedifference being that in the latter case, the pressure of the fluidbeing controlled, does not act on the piston to balance the valve, thebalancing effect being due to the similarity of conditions existing atthe opposite sides of the valve, or in other words, to the absence ofunequal pressures.

It will be seen that by varying the relative areas of the piston andvalve proper and the distance between them, the effect of the pressuremay be correspondingly varied according as the conditions encountered inpractice may demand.

Ordinarily I propose to make the valve 4- and the piston13-substantially equal in area so that the pressure in oppositedirections will be equal and the valve accurately balanced. In largevalves, where the connected valve and piston have considerable weight,and work in a vertical direction, the weight may be compensated for byreducing the size of the piston relatively to that of the valve, abalance being thereby preserved. In certain cases it may be desirable topartially balance the valve, which may be effected by differentiatingthe relative areas of the valve and piston, making either larger orsmaller than the other, according to the direction in which thepreponderance of pressure is to be applied; from which it will beunderstood that while my purpose is to provide a practically balancedvalve the relative areas of the parts through which the balancing isefiected may be varied to meet varying conditions encountered inpractice.

In Fig. 2 I have illustrated a modification of my invention. In thiscase instead of forming the communicating passage in the casing of thevalve as in the case first described, the passage is in the form of apipe extending at the opposite side of the casing. The operation of thisform of the valve is identical with that first described.

It is not necessary that the piston fit tightly within the chamber, andopenings 17 may be provided so that the movement of the piston and valvemay be free from undue friction.

I desire to be understood as treating the expression piston in thepresent case as synonymous with diaphragm and they are to be regarded asequivalents, as it is obvione that instead of the bodily moving of thepiston described, a flexible diaphragm may be employed, the operation inboth cases being identical as far as their, application in the presentinstance is concerned.

Having thus described my invention, I clain1- In a balanced valve thecombination of a casing having inlet and outlet ports, an annular valveseat between said ports, a pressure chamber opposite the valve seat, avalve fitted to said seat and movable in the direction of pressure,means for manually operating the valve, a piston or its describedequivalent in the pressure chamber connected with, and adapted to beoperated by, the valve operating means and substantially equal in areato the valve, a passage exterior to the valve seat and valve connectingthe inlet port with the pressure chamber beyond the piston therein, saidpassage constituting the sole communication between the pressure chamberand inlet port and means for controlling said passage independent of thevalve operating devices.

In testimony whereof I hereunto set my hand, this 31st day of May, 1893,in the presence of two attesting witnesses.

' LOUIS SCIlUlTE. iVitnesses:

DANIEL WATSON HILDRETH, MAURICE FRANCIS SPILLIN.

